Method of separating carbonaceous components from particulate coal containing inorganic solids and apparatus therefor

A method of separating the carbonaceous components of coal from the non-carbonaceous inorganic solids contained in previously formed agglomerates, which agglomerates are formed by agitating a first water slurry of particulate coal and oil to form the agglomerates and then separating the so formed agglomerates from the slurry, comprising the steps of:

• (1) mixing in water said previously formed agglomerates to form a second water slurry thereof;
• (2) sufficiently agitating the second slurry and positively introducing a sufficient amount of air into the second slurry to:
• (a) deagglomerate the previously formed agglomerates and separate the particulate coal from the inorganic solids;
• (b) allow the separated particulate coal to reagglomerate into more dense and robust reagglomerates than that of the previously formed agglomerates and have reduced amount of inorganic solids therein compared with the previously formed agglomerates;
• and
• (c) entrap sufficient air in and around the reagglomerates that the reagglomerates are more buoyant than the previously formed agglomerates;
• (3) allowing the reagglomerates to float to the top of the second water slurry;
• and
• (4) separating and recovering the reagglomerates with the reduced inorganic solids therein.